Burnishing tool



Ff. D. MONGEAU BURNISHING 'rooL Filed May 28, 1926 Patented Sept. 4, 1928.

UNITED STATES FRED D. MONGEAU, OF DEARBORN, MICHIGAN i BURNISHING TOOL.

Application led May 28,

This invention relates to the art of burnishing. An improved burnishing tool has been devised which constitutes the subject matter of this invention.

The tool may be used for burnishing such articles as valve lifter guides. If built on a larger scale it may be used to burnish engine cylinders or other large cylindrical walls.

It is an object of the invention to construct a burnishing tool for the purpose stated which shall be practically imperishable.

A further object is to provide for a convenient adjustment of the tool.

Another object is to provide means to burnish the hole by rotated balls.

A further provision of the tool is to arrange for automatically releasing the burnishing balls from operative position at the end of their travel. j

A still further object is to employ means within thertool to hold the burnishino` members retracted while the tool is being removed from the work.

The following description and the accompanying drawing are intended-to convey a full understanding of the invention.l .Y

In the drawing:

Figure 1 is a longitudinal section of the tool.

Figure 2 is a similar view showing the parts in a diiferent position.

Figure 3 is a transverse section on line 3--3 of Figure 1.

Figure 4 is a transverse section on line i-4 of Figure 1.

Figure 5 is a longitudinal section of a modification. Y

Referring by reference characters to the drawing, numeral l represents a hollow cylin drical body constituting the tool proper. Through this body 1 is inserted a rod 3. At one end the tool has an enlarged opening 5 closed by a plug 7, through which the rod 3 passes. Nut-s 9 9 -are adjustably threaded on this rod and between the nuts is a washer l1 of conical shape. Between the nuts and the washer on the .one hand and the plug 7 on the other, is a coil spring 13. This coil spring normally holds the rod 3 inwardly as in Figure 1 with the washer ll engaging a shoulder 12 of the tool member 1.

Means is provided to hold the rod in retracted position with spring 13 under compression. To that end the wall of part 1 is cut away7 at 15, as shown in Figure 4. A pin .17 extends longitudinally of the tool and 1926. Serial No. 112,319.

crosses the cut-away portion 15,1 and upon the l said pin 17 is pivoted a latch '19, having a tapered inn-er end. The latch is positioned to engage the washer 11 as the rod 3 moves to the right. The tapered ends of parts 11 and 19engage each other and as part 1l passes the latch i9 thelatch is swung down by a spring actuated plunger 21 mounted in a suitable recess in the tool member'. 1t will be seen from examination of Figure 2 that the fiat' faces of 19 and l1 are then in engagement and the rod 3 is held in retracted i position with spring 13 under compression..

At the working end, the tool is enlarged as at and to the enlarged vend is secured, by fastening means 27, a sleeve 29 which extends beyond the end of the tool where itl is pro-V vided with apertures 31 for the reception of balls These apertures are arranged in a circumferential series as shown in Figure 3. The diameter of the aperturesisless than that of the balls so that escape of the balls through the opening is prevented. The tool at the work end has a large opening 35 and within this opening the rod 3 is providedy with a bushing 37 which has an end portion'of its surface tapered as at 39 for the purposes ofv adjustment of the balls to a variable extent through the apertures of sleeve 29. A shoulder 39 and a nut 41 hold the bushing in position 0n rod 3. Tt is intended that the bush ing shall rotate upon rod 5 in the operation of the tool end, obviously, anti-friction means could be made use of between the bushing and the rod, if desired. y

Tt will be understood that in the operation of the devicethe latch mayy be manually de.- pressed, (see Figure 4) to permit the spring to thrust the rod 3 and the bushing^37 to the position shown by Figure 1. ln this position the washer 11 engages the shoulder o f the tool member' l. By suitablyv adjusting the nuts 9 and washer 11 the degree of projection of the burnishing balls may be deter` mined. The tool is then rotated by a lathe or other machin-e within a cylinder the interior wall of which is to be burnished. At

vthe end of its trayel the bushing is pushed back by engagement with any suitable stop against the compression of spring 13, thereby yallowing the burnishing balls to recede. By

scribed is intended more particularly for burnishing Walls ofcylinders or large open#V ings.

In Figure 5 is illustrated the simpler form for Working on smaller parts, Inthis form` the bushing is omitted and the tapered sur face is formed on the rod v3. In this case the rod under the pressure of the balls rotates, differing in this respect from the form described above Where the bushing rotates member having radial openings, burni'sliing,Y kmembers variably projectable in saidfopenings, axially movable means Within said tool, means biasing said movable means to hold said burn-ishingmembers in outward posi tion,m`eans to adjust said biasing position on said movable means to predetermine the projected position of said hurnishing members, said last named means beingV a member adjustable on said movable meansV and en gageable with a art of said tool under-the 'influence of said iasing means.

3. A burnishing toolcomprising a cylindrical tool member having radial apertures,

Y burnishing members in said apertures, movable means to variably move said burnishing members radially in said apertures, means to lock said movable means inA retracted position, said last; named means including a latch automatically engaging said movable means.

4. A burnishing Vtorol comprising a tool i member having radial apertures, burnishing members inv said a ertui'es, movable means Within the sai-d tool ravi-nga part to variably project Vsaid burnishing means radially in said apertures, amember adjustable on said `movable means, resilient means to bias said ltogether with a latch `to automaticall movable means to operative position by moving the `adjustable means against a fixed abutment. t A

5. The combination set forth in claim 4 lock said movable means in retracted position by engagement with said adjustable means.

j 6. A burnishing tool comprising a tool member having radial openings, burnishing members radially movable in sai-d openings, a member movable longitudinally through said tool, means on said movable member to project said burnishing memberradially yto j an extent depending upon the position of said movable member, adjusting meanson said movable member engageable with apart of said tool, resilient meansV to" movablyhold said adjustable means in engagement withV said tool and the burnishing members projected, and a manually releasable latch automatically engageable with said adjustable .means wlien the movable means is retracted against the compression or' the resilient means.y i Y 7. A burnishing tool comprising a tool member, bui'nishing means radially movable relativethereto, resilient means toliold said burnisliing means in L projected position-,f

means-to pre-determine the extent of such radial projection, and ineansto lock said resilient means under compression to permit the Withdrawal of said burnishing means.

8. A buriiishingy tool comprising a tool.

member, burnishing means radially movable therein, reciprocating means in said tool" member, a tapered bushing rotatableon said reciprocating meansA and engaging said burnishing means to variably project `lilies-ame, together with resilient means to normally project said burnishing means and antoinati cally loperative means to lock said reciprocating means in retracted position. j

'9. A burnishing tool vcomprising a tool member, burnishing means radially movable 'i i therein, reciprocating means in said tool, a

taperedbushing on said reciprocating means j engaging said burnishing means to -variably project the saine, `and resilient means to pro ject said burnishing' means and means adjustably carried by said reciprocating .inea-ns1 and engaging an abutment on said tool ber to predetermine the radial projection of said burnishing means. l

l0. A burnishing tool comprising a tool` member, `burnishing means radially movable therein, reciprocating'means in said tool, a tapered bushing on saidreciprocating `means engaging said burnishing means rtovariably project the same, resilient means to reciprocate said burnishing means, 'and means comprising automatically engaging partsY onsaid tool member and saidreciprocatiiigmember to-lock said reciprocating member Iin retracted position, one ot'sai-d interengagin-g partsba Y ing longitudinafllj7 adjustable.

` l1. VA burnishing tool comprising a tool member, 4burnishing means radially movable therein, reciprocating means in said tool',-a

tapered bushingon said reciprocating means and yengaging said burnishing means to va-` riably retract' the same, resilient means to 4 normally projectsaid burnishing` means and automatically"operative mechanism to lock said reciprocating means in retracted position, said mechanism comprising a-stop`longitudinally adjustable `on vsaid reciprocating Lneans anda pivotallateh on sai-d tool memel'. i

In testimony whereof I affix my signature; FRED D. MONGEAU.

izo 

